| irritable | grouchy |
| irritant | galling |
| irritation | annoyance |
| irritation due à la chaleur | heat rash |
| irriter | annoy |
| irrité | mad |
| Irrlicht | Irrlicht Engine |
| irruption | efflorescence |
| irréalisable | impracticable |
| irréaliste | unrealistic |
| irréconciliable | irreconcilable |
| irrécouvrable | irrecoverable |
| irrécupérable | irrecoverable |
| irrécusable | airtight |
| Irrédentisme | Irredentism |
| irréductible | irreducible |
| irréel | unreal |
| irréflexion | indiscretion |
| irréfléchi | unguarded |
| irréfragable | airtight |
| irréfutable | positive |
| irréfutablement | undeniably |
| irrégularité | unstableness |
| irrégulier | abnormal |
| irrégulièrement | erratically |
| irréligieux | ungodly |
| irrémédiable | irredeemable |
| irrémédiablement perdu | irretrievably lost |
| irréparable | irreparable |
| irrépressible | uncontrollable |
| irréprochable | unblemished |
| irrépréhensible | unexceptionable |
| irrésistible | uncontrollable |
| Irrésistible Alfie | Alfie |
| irrésistiblement | uncontrollably |
| irrésolu | dubious |
| irrésolution | indecision |
| irréversibilité du phénomène | irreversibility of the phenomenon |
| irrévocable | final |
| irrévocablement perdu | lost beyond recall |
| irrévérence | disrespect |
| irrévérencieux | ill-mannered |
| Irtych | Irtysh River |
| Irulan | Irulan Corrino |
| Irun | Irun |
| Irurtzun | Irurtzun |
| Irvine Welsh | Irvine Welsh |
| Irving Berlin | Irving Berlin |
| Irving Fisher | Irving Fisher |
| Irving Langmuir | Irving Langmuir |
| Irving Stone | Irving Stone |
| Irving Thalberg | Irving Thalberg |
| Irwin Rose | Irwin Rose |
| Irwin Shaw | Irwin Shaw |
| Irwin Winkler | Irwin Winkler |
| Iry-Ro | Iry-Hor |
| Iráklion | Heraklion |
| Irène Jacob | Irène Jacob |
| Irène Joliot-Curie | Irène Joliot-Curie |
| Irène Némirovsky | Irène Némirovsky |
| Irène Papas | Irene Papas |
| Irénée de Lyon | Irenaeus |
| Irénée Ier de Jérusalem | Patriarch Irenaios |
| IS | IS |
| IS-IS | IS-IS |
| ISA | ISA |
| İsa Qəmbər | Isa Gambar |
| Isaac | Isaac |
